EP0011495A1 - Verfahren und Apparat zum Antreiben einer Informationsspeicherplatte - Google Patents

Verfahren und Apparat zum Antreiben einer Informationsspeicherplatte Download PDF

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Publication number
EP0011495A1
EP0011495A1 EP79302594A EP79302594A EP0011495A1 EP 0011495 A1 EP0011495 A1 EP 0011495A1 EP 79302594 A EP79302594 A EP 79302594A EP 79302594 A EP79302594 A EP 79302594A EP 0011495 A1 EP0011495 A1 EP 0011495A1
Authority
EP
European Patent Office
Prior art keywords
disc
information
velocity
signal
transducer
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP79302594A
Other languages
English (en)
French (fr)
Other versions
EP0011495B1 (de
EP0011495B2 (de
Inventor
Wayne Ray Dakin
Ludwig Ceshkovsky
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Discovision Associates
Original Assignee
Discovision Associates
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=25504432&utm_source=***_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=EP0011495(A1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Discovision Associates filed Critical Discovision Associates
Priority to AT79302594T priority Critical patent/ATE9417T1/de
Publication of EP0011495A1 publication Critical patent/EP0011495A1/de
Publication of EP0011495B1 publication Critical patent/EP0011495B1/de
Application granted granted Critical
Publication of EP0011495B2 publication Critical patent/EP0011495B2/de
Expired legal-status Critical Current

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Classifications

    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B19/00—Driving, starting, stopping record carriers not specifically of filamentary or web form, or of supports therefor; Control thereof; Control of operating function ; Driving both disc and head
    • G11B19/20—Driving; Starting; Stopping; Control thereof
    • G11B19/24—Arrangements for providing constant relative speed between record carrier and head

Definitions

  • This invention relates generally to information storage discs and, more particularly, to apparatus for rotating an information disc relative to a radially movable transducer.
  • Discs for storing large quantities of video information have come into increasing usage in recent years as a result of an increasing need for storage media that provide instantaneous playback, fast random access, and relatively high recording density.
  • the information is typically encoded on the disc in the form of an optically readable sequence of light-reflective and light-scattering regions arranged in substantially circular tracks forming a spiral or concentric circular pattern over the information- bearing surface of the disc.
  • the light-reflective and light-scattering regions are initially formed in the disc using an optical transducer for directing onto the disc a collimated beam of high intensity light that is modulated by the information to be recorded.
  • the disc is rotated about its central axis at a substantially constant angular velocity relative to the transducer, while the beam of light is moved radially with respect to the disc at a relatively slow, but constant, velocity.
  • Each revolution of the disc thus results in the production of a separate, substantially circular information track.
  • the disc is ordinarily rotated at approximately 1800 r.p.m., whereby each information track contains the information for one video frame.
  • a typical system for rotating a disc at a constant angular velocity includes an oscillator for producing a reference signal having a prescribed constant frequency, and a servo for locking the angular velocity of the disc onto the frequency of the reference signal.
  • the servo typically includes a spindle motor for rotating the disc, and AC tachometer coupled to the motor for producing a signal having a frequency indicative of the angular velocity of the motor and a phase detector for comparing the tachometer signal with the reference signal and producing a control signal proportional to the difference in their respective phase angles.
  • This control signal is suitably processed in a compensation circuit for producing a prescribed frequency response for the servo, and, in turn, amplified and coupled to the spindle motor to appropriately control its angular velocity.
  • the present invention is embodied in an improved apparatus, and a related method, for controlling the angular velocity of an information storage disc having a plurality of substantially circular and concentrically arranged information tracks.
  • the disc is controllably rotated relative to a radially movable transducer postioned in a prescribed relationship relative to a selected one of the information tracks, whereby the transducer can either record or playback information from that track.
  • the apparatus includes means for reducing the angular velocity of the disc as the radius of the selected information track increases whereby a greater density of information can be stored on the disc than if the angular velocity of the disc were maintained constant.
  • the apparatus further includes means for correspondingly reducing the radial velocity of the transducer as the radius of the selected track increases, whereby the tracks are substantially equally spaced with respect to each other. Further, by making the angular velocity of the disc inversely proportional to the radius of the selected track, the track will be moved at a constant linear velocity relative to the transducer, and a uniformly high recording density over the entire surface of the disc can be achieved.
  • an apparatus constructed in accordance with the present invention is especially adapted for use in an information storage diss mastering machine, wherein information is recorded anto the disc by an optical transducer.
  • the transducer produces a collimated beam of light, which is modulatei with the information to be recorded, and which is firected by a focusing lens onto a selected portion of the disc, as the disc is controllably rotated with respect to it.
  • the lens is attached to a carriage that is rafially movable relative to the disc by a lead screw, to direct the light beam onto the selected information track.
  • the means for producing a measure of radius includes a potentiometer coupled to the movable lens carriage and appropriately connected to produce an analog voltage signal that varies inversely with the radius of the selected track.
  • This analog voltage signal is applied to a voltage-controlled oscillator (VCO) to produce a velocity signal having a frequency substantially inversely proportional to the radius of the selected track.
  • VCO voltage-controlled oscillator
  • the velocity signal produced by the VCO is applied to a spindle motor servo for synchronizing the angular velocity of a spindle motor that rotates the disc witn instantaneous frequency of the velority signal, whereby the disc is moved at a substarrially constant linear velocity relative to the transducer.
  • the velocity signal is coupled to a lens carriage driver for controllably rotating the lead screw, and thereby moving the focusing lens in a radial direction, at a corresponding velocity proportional to the frequency of the velocity signal.
  • FIG. 1 there is shown a servo apparatus for rotating an information storage disc 11 about its central axis 13 at a precisely controlled angular velocity.
  • the disc 11 is rotated relative to an optical transducer 15, which operates to record onto the disc information suchas a conventional color television signal frequency modulated on a carrier.
  • the optical transducer 15 includes means for producing a collimated beam of light (not shown) modulated by the information to be recorded, along with a lens carriage 17, which is controllably movable by a lead screw 19, in a radial direction relative to the disc 11, to direct the light beam onto a selected portion of the disc as the disc is rotated with respect to it.
  • This produces a series of substantially circular information tracks (see FIGURE 2) forming a spiral on the surface of the disc, each track comprising an alternating sequence of light-reflective regions 21 and light-scattering regions 23 (FIGURE 3).
  • the servo apparatus is shown to include means for producing a velocity signal having a frequency corresponding to the desired angular velocity of the information storage disc 11, along with a spindle motor servo 25, responsive to the velocity signal, for controllably rotating the disc at a corresponding angular velocity.
  • the velocity signal has an instantaneous frequency substantially inversely proportional to the radius of the information track being recorded, whereby the track is moved at a substantially constant linear velocity relative to the lens carriage 17 and a uniform information recording density over the entire surface of the disc is achieved.
  • the apparatus of FIGURE 1 further includes a lens carriage driver 37, responsive to the velocity signal, for moving the lens carriage 17 radially relative to the disc 11 at a velocity corresponding to the frequency of the signal.
  • a lens carriage driver 37 responsive to the velocity signal, for moving the lens carriage 17 radially relative to the disc 11 at a velocity corresponding to the frequency of the signal.
  • FIGURE 2 shows, in schematic form, one frame 27 of the video signal, extending over one complete information track near the center of the disc 11, along with a plurality of consecutive video signal frames 29, 31, 33, and 35 extending over a pair of tracks located near the periphery of the disc, each of these latter frames extending over substantially less than a complete circumference of the disc.
  • FIGURE 3 shows, in enlarged form, the successive light-reflective and light-scattering regions 21 and 23 for a portion of the video signal frame designated 27, along with corresponding regions 21' and 23' for a portion of the frame designated 33. It should be noted that, since each video signal frame recorded on the disc 11 is substantially of equal lengths of the respective light-scattering regions 23 and 23' are, likewise, substantially equal. Thus, a maximum information recording density over the entire surface of the disc 11 can be maintained, and the disc can be used to store a substantially longer-playing video signal than was possible with conventional constant angular velocity discs.
  • the velocity signal which as a frequency inversely proportional to the radius of the information track being recorded, is produced by a voltage-controlled oscillator (VCO) 39 that is controlled by a control signal received over line 41 from an amplifier circuit 43.
  • VCO voltage-controlled oscillator
  • This amplifier circuit is appropriately coupled to the lead screw 19, such that as the lens carriage 17 is moved radially, the voltage of the control signal will automatically vary substantially inversely with the radius of the information track being recorded.
  • the VCO 39 generates a frequency substantially directly proportional to the voltage of the control signal input, so the frequency of the velocity signal produced by the VCO will likewise vary substantially inversely with the radius of the information track being recorded.
  • the VCO 39 generates a frequency substantially directly proportional to the voltage of the control signal input, so the frequency of the velocity signal produced by the VCO will likewise vary substantially inversely with the radius of the track being recorded.
  • the amplifier 43 includes a conventional operational amplifier 47, with a fixed resistor 49 coupled between its output and negative input terminals, and with a potentiometer 45 coupled between its negative input terminal and a fixed voltage reference +V REF .
  • the potentiometer is mechanically coupled to the lead screw 19 that moved the lens carriage 17 and is adapted to produce an electrical current that varies inversely the radius of the lens carriage, whereby the control anal produced by the amplifier 43 has a voltage likewise inversely proportional to the radius.
  • the spindle motor servo 25 operates in a conventional manner to synchronize the angular velocity of the disc 11 with the varying frequency of the velocity signal, whereby the disc is moved at a substantially constant linear velocity relative to the lens carriage 17.
  • the servo further includes a phase detector 55 for comparing the respective phase angles of the tachometer signal, supplied over line 57 from the tachometer, and the velocity signal, supplied on line 59 from the VCO 39, thereby producing a control signal proportional to the phase difference.
  • This control signal is transmitted over line 61 to a conventional phase and amplitude compensator 63, and, in turn, over line 65 to an amplifier 67.
  • the output of the amplifier is coupled over line 69 to the spindle motor 51 to appropriately control its angular velocity.
  • the lens carriage driver 37 operates in a conventional manner to drive the lens carriage 17 in a radial direction relative to the disc 11, at a velocity that corresponds to the frequency of the velocity signal.
  • the driver 37 includes a divide-by-N circuit 71 for frequency dividing the velocity signal, supplied on line 59 from the VCO 39, to produce a carriage velocity control signal having a proportionately lower frequency.
  • This carriage velocity control signal is transmitted over line 73 to an amplifier 75, and, in turn, over line 77 to a synchronous lens carriage tor 79.for appropriately rotating the lead screw 15 to controllably move the lens carriage in a radial direction relative to the information disc 11.
  • the radial velocity of the lens carriage is made to be inversely proportional to the radius of the information track being recorded, and the successive tracks will be substantially equally spaced with respect to each other.
  • the present invention provides an effective apparatus for recording information on an information storage disc, wherein the information is stored in a series of substantially circular and concentrically. arranged information tracks, at a.substantially.constant recording density.
  • the information storage disc is rotated at an angular velocity substantially inversely proportional to the radius of the particular information track being recorded, whereby an approximately constant linear velocity of the disc relative to an optical transducer is maintained, and, additionally, the transducer is moved radially relative to the disc at a corresponding radial velocity substantially inversely proportional to the radius of the selected track, whereby the successive tracks are approximately equally spaced with respect to each other.
  • the apparatus operates to record a substantially greater amount of information on the disc than does a conventional constant angular velocity apparatus, and when used to record video information, discs having a substantially longer playing time will be produced.

Landscapes

  • Rotational Drive Of Disk (AREA)
  • Optical Recording Or Reproduction (AREA)
  • Manufacturing Optical Record Carriers (AREA)
  • Management Or Editing Of Information On Record Carriers (AREA)
  • Signal Processing For Digital Recording And Reproducing (AREA)
EP79302594A 1978-11-16 1979-11-15 Verfahren und Apparat zum Antreiben einer Informationsspeicherplatte Expired EP0011495B2 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT79302594T ATE9417T1 (de) 1978-11-16 1979-11-15 Verfahren und apparat zum antreiben einer informationsspeicherplatte.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US05/961,405 US4228326A (en) 1978-11-16 1978-11-16 System for recording information on a rotatable storage disc, in a substantially uniform recording density
US961405 1978-11-16

Publications (3)

Publication Number Publication Date
EP0011495A1 true EP0011495A1 (de) 1980-05-28
EP0011495B1 EP0011495B1 (de) 1984-09-12
EP0011495B2 EP0011495B2 (de) 1989-07-12

Family

ID=25504432

Family Applications (1)

Application Number Title Priority Date Filing Date
EP79302594A Expired EP0011495B2 (de) 1978-11-16 1979-11-15 Verfahren und Apparat zum Antreiben einer Informationsspeicherplatte

Country Status (11)

Country Link
US (1) US4228326A (de)
EP (1) EP0011495B2 (de)
JP (1) JPS6014421B2 (de)
AT (1) ATE9417T1 (de)
AU (1) AU532366B2 (de)
BR (1) BR7907413A (de)
CA (1) CA1143061A (de)
DE (1) DE2967217D1 (de)
HK (1) HK49586A (de)
MY (1) MY8700147A (de)
SG (1) SG14086G (de)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0018156A1 (de) * 1979-04-17 1980-10-29 BURROUGHS CORPORATION (a Delaware corporation) Rotierende Aufzeichnungsträger verwendender Aufzeichnungs- und Wiedergabeapparat
EP0023845A1 (de) * 1979-08-06 1981-02-11 Victor Company Of Japan, Limited Gerät zur Aufnahme eines Signals mit konstanter relativer linearer Aufzeichnungsgeschwindigkeit auf ein rotierendes Aufnahmemedium
EP0227071A2 (de) * 1985-12-20 1987-07-01 Sony Corporation Vorrichtung zum Abspielen von Videoplatten
EP0745992A2 (de) 1991-12-23 1996-12-04 Nimbus Communications International Limited Plattenspeicherungsanlage und Rotationssteuerungsverfahren dafür
WO1997037349A1 (en) * 1996-04-01 1997-10-09 International Business Machines Corporation Power saving method and apparatus for use in multiple frequency zone drives
AU694947B2 (en) * 1993-02-02 1998-08-06 Nimbus Communications International Limited A disk recording system

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JPS5787371U (de) * 1980-11-17 1982-05-29
JPS57198586A (en) * 1981-05-28 1982-12-06 Sony Corp Digital disc reproducing device
JPS57198579A (en) * 1981-05-29 1982-12-06 Sony Corp Disc reproducing device
JPS57208639A (en) * 1981-06-18 1982-12-21 Toshiba Corp Recording method of disk
JPS5812149A (ja) * 1981-07-15 1983-01-24 Nippon Columbia Co Ltd ビデオ・デイスク及びその記録装置
JPS5819767A (ja) * 1981-07-29 1983-02-04 Nec Home Electronics Ltd 回転記録媒体の等線速度制御装置
JPS58101358U (ja) * 1981-12-29 1983-07-09 日本圧電気株式会社 光学式情報読取装置
JPS58175109A (ja) * 1982-04-07 1983-10-14 Pioneer Video Kk 円盤状記録媒体の記録方式
JPS59127271A (ja) * 1983-01-07 1984-07-23 Canon Inc トランスデユ−サの送り装置
JPS6070563A (ja) * 1983-09-27 1985-04-22 Toshiba Corp 高密度螺旋描画装置
JPS61129778A (ja) * 1984-11-28 1986-06-17 Pioneer Electronic Corp デイスク再生方式
JPS6254868A (ja) * 1985-09-03 1987-03-10 Victor Co Of Japan Ltd 回転記録媒体の回転数制御装置
JP2630375B2 (ja) * 1986-02-28 1997-07-16 パイオニア株式会社 アドレス探索機能を有する情報再生装置
GB8906353D0 (en) * 1989-03-20 1989-05-04 Dewar Productions Inc Semi-timing optic lathe
US6141300A (en) * 1989-06-20 2000-10-31 Discovision Associates Optical actuator including lens assembly with optical axis having symmetric suspensory forces acting thereon and optical disc system including same
US5265079A (en) 1991-02-15 1993-11-23 Applied Magnetics Corporation Seek actuator for optical recording
US5182741A (en) * 1989-08-25 1993-01-26 Sharp Kabushiki Kaisha Optical disk recording/reproducing device utilizing a constant angular velocity method with a constant linear velocity formatted optical disk
US6236625B1 (en) 1991-02-15 2001-05-22 Discovision Associates Optical disc system having current monitoring circuit with controller for laser driver and method for operating same
US6069857A (en) * 1991-02-15 2000-05-30 Discovision Associates Optical disc system having improved circuitry for performing blank sector check on readable disc
US5729511A (en) * 1991-02-15 1998-03-17 Discovision Associates Optical disc system having servo motor and servo error detection assembly operated relative to monitored quad sum signal
US5808980A (en) * 1991-02-15 1998-09-15 Discovision Associates Seek actuator for optical recording
US5677899A (en) * 1991-02-15 1997-10-14 Discovision Associates Method for moving carriage assembly from initial position to target position relative to storage medium
US5590102A (en) * 1995-01-12 1996-12-31 Discovision Associates Recording informatioin on an optical disc without using pre-manufactured tracks
US6434087B1 (en) 1995-01-25 2002-08-13 Discovision Associates Optical disc system and method for controlling bias coil and light source to process information on a storage medium
US6091684A (en) * 1995-01-25 2000-07-18 Discovision Associates Optical disc system and method for changing the rotational rate of an information storage medium
US5920539A (en) * 1995-01-25 1999-07-06 Discovision Associates Apparatus and method for suppression of electromagnetic emissions having a groove on an external surface for passing an electrical conductor
US5748578A (en) * 1995-01-25 1998-05-05 Discovision Associates Colpitts type oscillator having reduced ringing and improved optical disc system utilizing same
US5978329A (en) * 1995-06-07 1999-11-02 Discovision Associates Technique for closed loop servo operation in optical disc tracking control
ES2112224T1 (es) * 1995-12-06 1998-04-01 Discovision Ass Aparato y metodo para control de foco.
US5689485A (en) 1996-04-01 1997-11-18 Discovision Associates Tracking control apparatus and method
US5808990A (en) * 1996-12-17 1998-09-15 Cinram, Inc. Method and apparatus for controlling the linear velocity between an optical head and a rotation disk
US6768709B2 (en) 2000-02-23 2004-07-27 Doug Carson & Associates, Inc. Hiding digital data in a digital audio or video carrier signal
KR100379750B1 (ko) * 2000-06-30 2003-04-16 주승용 골프용 티이의 구조
US6477124B2 (en) 2000-11-15 2002-11-05 Doug Carson & Associates, Inc. Varying the rate at which data appear on an optical disc rotated at a constant linear velocity to prevent unauthorized duplication of the disc
US7568081B2 (en) * 2000-11-15 2009-07-28 Doug Carson & Associates, Inc. Authenticating a data storage medium using predetermined inter-sector relationships
JP2004265491A (ja) * 2003-02-28 2004-09-24 Matsushita Electric Ind Co Ltd 情報記録媒体の回転速度制御装置
US7522481B2 (en) * 2004-10-28 2009-04-21 Koninklijke Philips Electronics N.V. Disc drive mechanism and method of operation therefor
US20060250977A1 (en) * 2005-05-04 2006-11-09 International Business Machines Corporation Method and apparatus for determining data center resource availablilty using multiple time domain segments

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DE2521821A1 (de) * 1975-05-16 1976-11-25 Bosch Gmbh Robert Videoplattengeraet
US4079942A (en) * 1975-09-11 1978-03-21 Edward A. Jazlowiecki Method of and apparatus for controlling turntable speed
DE2811761A1 (de) * 1978-03-17 1979-09-20 Wilhelm Dr Ing Lepper Verfahren zur aufnahme und wiedergabe von schallaufzeichnungen fuer schallplatten und einrichtung zur durchfuehrung des verfahrens

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DE1562038B2 (de) * 1968-02-13 1971-05-13 Telefunken Patentverwertungsgesell schaft mbH, 790OUIm System zur aufzeichnung und abtastung von bildsignalen und der bildwechselfrequenz entsprechenden impulsen unter ver wendung eines plattenfoermigen aufzeichnungstraegers
JPS4875002A (de) * 1972-01-05 1973-10-09
DE2257817A1 (de) * 1972-11-25 1974-05-30 Hubertus Wentzell Aufzeichnungs- und wiedergabeverfahren fuer platten-informationstraeger
JPS5841710B2 (ja) * 1973-03-16 1983-09-13 ソニー株式会社 ジヨウホウシンゴウキロクホウホウ
GB1572346A (en) * 1976-03-19 1980-07-30 Rca Corp Velocity and phase control for a disc recording and reproducing apparatus

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2208161A1 (de) * 1972-11-29 1974-06-21 Ibm
DE2521821A1 (de) * 1975-05-16 1976-11-25 Bosch Gmbh Robert Videoplattengeraet
US4079942A (en) * 1975-09-11 1978-03-21 Edward A. Jazlowiecki Method of and apparatus for controlling turntable speed
DE2811761A1 (de) * 1978-03-17 1979-09-20 Wilhelm Dr Ing Lepper Verfahren zur aufnahme und wiedergabe von schallaufzeichnungen fuer schallplatten und einrichtung zur durchfuehrung des verfahrens

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0018156A1 (de) * 1979-04-17 1980-10-29 BURROUGHS CORPORATION (a Delaware corporation) Rotierende Aufzeichnungsträger verwendender Aufzeichnungs- und Wiedergabeapparat
EP0023845A1 (de) * 1979-08-06 1981-02-11 Victor Company Of Japan, Limited Gerät zur Aufnahme eines Signals mit konstanter relativer linearer Aufzeichnungsgeschwindigkeit auf ein rotierendes Aufnahmemedium
EP0227071A2 (de) * 1985-12-20 1987-07-01 Sony Corporation Vorrichtung zum Abspielen von Videoplatten
EP0227071A3 (en) * 1985-12-20 1989-02-22 Sony Corporation Video disc reproducing apparatus
EP0745992A2 (de) 1991-12-23 1996-12-04 Nimbus Communications International Limited Plattenspeicherungsanlage und Rotationssteuerungsverfahren dafür
AU694947B2 (en) * 1993-02-02 1998-08-06 Nimbus Communications International Limited A disk recording system
WO1997037349A1 (en) * 1996-04-01 1997-10-09 International Business Machines Corporation Power saving method and apparatus for use in multiple frequency zone drives
US5787292A (en) * 1996-04-01 1998-07-28 International Business Machines Corporation Power saving method and apparatus for use in multiple frequency zone drives

Also Published As

Publication number Publication date
HK49586A (en) 1986-07-11
EP0011495B1 (de) 1984-09-12
SG14086G (en) 1990-08-17
MY8700147A (en) 1987-12-31
AU5284479A (en) 1980-05-22
DE2967217D1 (en) 1984-10-18
CA1143061A (en) 1983-03-15
BR7907413A (pt) 1980-07-22
JPS55101162A (en) 1980-08-01
JPS6014421B2 (ja) 1985-04-13
EP0011495B2 (de) 1989-07-12
ATE9417T1 (de) 1984-09-15
US4228326A (en) 1980-10-14
AU532366B2 (en) 1983-09-29

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